Casing for a hot box or blocked brake detection scanner

ABSTRACT

The invention relates to a casing for a hot box or blocked brake detection scanner ( 2 ) comprising infrared detectors and a heating means, wherein the casing is comprised of a casing lower part and a lid ( 5 ), the lid ( 5 ) is designed as a chimney top with lateral surfaces ( 7, 8 ) converging towards the upper edge and carrying an electrical heating means ( 4 ) on their inner sides ( 6 ), and the lid ( 5 ) includes openings ( 9 ) for the scanning geometry of the infrared detector(s) on its upper edge or near its upper edge.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a casing which includes a heating means for ahot box or blocked brake detection scanner comprising infrareddetectors. The casing is attached to a track section.

2. Prior Art

Hot box or blocked brake detection scanners usually are mounted to railswith the measuring openings of the detectors being at a relativelyslight distance relative to the rail upper edge. Such a slight distancein case of a snow or ice covering, as a rule, will not constitute amajor problem if the layer of snow above the detector is melted by aheating means incorporated in the scanning means. Due to the slightdistance, the upper edges of such detectors are cleaned by the relativewind produced by rolling rail vehicles. Known such devices have beendescribed in DE-A-19 18 317, wherein a special supporting structure isscrewed to the rail webs and the respective hot box or blocked brakedetection means is mounted to the supporting structure.

DE-A-42 17 681 has already suggested the installation of hot boxdetection scanners or blocked brake detection scanners in atrough-shaped sleeper. The upper edge of such trough-shaped sleepers islocated on the level of the rail foot and the hot box or blocked brakedetection scanners are, therefore, immersed in the trough-shapedsleeper, from which results a relatively large distance between theupper edge of the rail and the measuring means. With such a largedistance, larger amounts of snow or ice may build up above the detector,thus impairing or even preventing measurements.

SUMMARY OP THE INVENTION

The invention aims at providing a casing of the initially defined kind,which is suitable for being incorporated in a trough-shaped sleeperwhich safely utilizes the advantages of an installation directly in thetrough-shaped sleeper even in adverse meteorological conditions and, inparticular, when intensive snow fall or the like is likely to build up athick layer of snow or ice on the detector. To solve this problem, theconfiguration according to the invention essentially consists in thecasing being comprised of a casing lower part and a lid, the lid beingdesigned as a chimney top with lateral surfaces converging towards theupper thereof and carrying an electrical heating means on their innersides. The lid includes openings for the scanning beams of one or moreinfrared detectors on its upper edge or near its upper edge. Byproviding, in addition to a casing lower part which, in accordance witha preferred further development of the invention, is formed by thetrough-shaped sleeper itself and a lid which is designed as a chimneytop having lateral surfaces converging towards the upper edge, it isensured that even in case of heavy snow fall, the snow will descendalong the converging lateral surfaces under the action of gravity. Byproviding electrical heating means on the inner sides of the lateralsurfaces and openings for the scanning beams of the infrared detector inthe lid on its upper edge or near its upper edge, it is ensured that theintegrated heating reliably keeps clear from snow or ice the respectiveopening cross section on the upper side of the lid by ascending hot airso as to allow the safe scanning and detection of hot boxes or blockedbrakes. The surface available for a possible snow cover is relativelysmall, since that surface directly merges into the laterally slopinglateral surfaces converging towards the upper edge. By heating thoselateral surfaces, at least a film of snow in direct contact with thelateral walls will melt such that the snow load can descend under itsown weight and melt subsequently. Due to a stacking effect, the openingson the upper edge are safely kept clear even at a comparatively lowheating performance, since, bearing in mind the small upper surface, theoverall amount of snow or ice built up thereabove remains relativelysmall. This applies all the more, since the upper edge of the casing lidis brought near the travelling edges of the rail due to the chimney topsuch that even the relative wind of rolling rail vehicles will cause anadditional mechanical cleaning effect. Advantageously, the configurationis devised such that the casing lower part comprises a furtherelectrical heating means and is provided with discharge openings formelt water so as to prevent major amounts of snow from collecting in theinterior of the upwardly open casing.

In a particularly simple manner, the heating means of the lid isdesigned as an electrical resistance heater having windings which extendsubstantially parallel with the bottom of the casing lower part. Such anarrangement of the electrical resistance heater directly results in thedesired flow course of the ascending hot air, thus ensuring particularlyefficient clearing of snow even at low heating performances.

In order to further, enhance mechanical cleaning by rolling railvehicles, the track section with the casing attached theretoadvantageously is devised such that the track section comprises atrough-shaped sleeper, that the casing is arranged in the trough-shapedsleeper, that the upper edge of the lid is arranged at a distance fromthe upper edge of the sleeper, which distance corresponds to thesmallest admissible free space or clear space between the plane of therail upper edge and the hot box detection scanner or blocked brakedetection scanner. In order to ensure the correct orientation of thescanning beams and better take into account the geometrical conditionsof hot box or blocked brake detection scanners installed in atrough-shaped sleeper, the configuration advantageously is devised suchthat the lid, in a cross-sectional plane through which the axis of thetrough-shaped sleeper passes, is designed to be asymmetricallytrapezoidal and that the upper surface, which is parallel to the planeof the rail travelling edges, is located in the projection on thetrough-shaped sleepers of the bearings of a rolling rail is vehicle tobe detected.

In a particularly simple manner, the casing lower part, as alreadymentioned, may be designed as a partial region of the trough-shapedsleeper and the lid may extend over the total width of the trough-shapedsleeper, viewed in the longitudinal direction of the rail, and befixable thereto. In that case it will do to appropriately spot-drill,and provide with a thread, the end faces of the side walls of thetrough-shaped sleeper such that the lid can be directly screwed andplaced on the trough-shaped sleeper. Trough-shaped sleepers are usuallyprovided with covers and the same means as are provided for fixing thecovers of the trough-shaped sleeper may also be used for fastening thelid, including the chimney top

In order to render the penetration or pressing in of snow or the likeeven more difficult, the configuration advantageously is devised suchthat the openings of the lid are equipped with closeable covers. Thecloseable covers may be formed by simple slides or flaps connected withan actuator, the opening of the covers being effected during thescanning procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following description, the invention will be explained in moredetail by way of an exemplary embodiment schematically illustrated inthe drawing. Therein, FIG. 1 is a perspective illustration of an openedtrough-shaped sleeper with the lid being removed and hot box detectionscanners being inserted, and FIG. 2 shows the illustration according toFIG. 1 with the lid being closed.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

From FIG. 1 a trough-shaped sleeper 1 is apparent, in which hot boxdetection scanners 2 are inserted. A heating means 4 is provided withinthe lid of the trough-shaped sleeper, a connecting cable 3 for theheating means 4 being visible in the lid 5. The heating means 4 providedin the lid is designed as a resistance heater which extends over theinner sides 6 of the lid side walls as denoted by 7 and 8 in FIG. 2. Asis apparent, in particular, from FIG. 2, the upper edge of the lidincludes openings 9 so that the required scanning geometry of thescanner on the bearings of a rolling rail vehicle can be ensured. InFIGS. 1 and 2, the rail is denoted by 10, wherein just one rail isdepicted in each case. The trough-shaped sleeper 1 extends over thetotal width of the track. As is apparent from FIG. 2, the trough-shapedsleeper is closed by a plane lid 11 by means of screws 12. On thelaterally protruding parts of the trough-shaped sleeper, in which thehot box detection means 2 is arranged, the lid 13 comprises two lateralsurfaces 7 and 8 converging towards the upper edge, wherein the openings9 are provided in a top surface 14 extending parallel to the upper edgeof the rails 10. Due to the chimney-like top comprising mutuallyconverging side walls 7 and 8, the area of the plane top surface 14 isextremely small and can be reliably cleared by the relative wind. Theopenings 9 are reliably kept clear of snow and ice by the heating meansarranged on the internal walls 6 of the side walls 7 and 8 and by thestack effect caused by the same.

What is claimed is:
 1. A casing for a hot box or a blocked brakedetection scanner having at least one infrared detector and anelectrical heating means, wherein the casing comprises a base portioncovered by a lid having inclined lateral surfaces converging towards anupper edge and carrying said heating means on inner sides of saidsurfaces, and wherein the lid includes at least one opening foraccommodating a scanning geometry of the infrared detector on at leastone of said upper edge and an inclined surface adjacent said upper edge.2. A casing according to claim 1, wherein the base portion is capable ofcarrying a further electrical heating means.
 3. A casing according toclaim 1 or 2, wherein the heating means within the lid is an electricalresistance heater extending substantially parallel with the baseportion.
 4. A casing according to claim 1 or 2, wherein the upper edgeof the lid, when said base portion of the casing is located on a sleeperwhich underlies a rail, is disposed at a distance from an upper edge ofthe sleeper which minimizes a space between the plane of a rail upperedge and the detection scanner.
 5. A casing according to claim 4,wherein the lid, when viewed in a plane normal to the longitudinal axisof the trough-shaped sleeper, is asymmetrically trapezoidal, and anupper surface of the lid is parallel to a plane of an upper edge of therail and is located below bearings of a rolling rail vehicle travelingon said rail.
 6. A casing according to claim 4, wherein the casing baseportion is formed from a region of a trough-shaped sleeper, and the lidextends over a total width of the sleeper, as viewed in a longitudinaldirection of the rail, and is fixed to the base portion.
 7. A casingaccording to claim 1 or 2, wherein the opening of the lid is configuredto be covered by a closable cover.
 8. A casing according to claim 3,wherein the upper edge of the lid, when said base portion of the casingis located on a sleeper which underlies a rail, is disposed at adistance from an upper edge of the sleeper which minimizes a spacebetween the plane of a rail upper edge and the detection scanner.
 9. Acasing according to claim 8, wherein the lid, when viewed in a planenormal to the longitudinal axis of a trough-shaped sleeper, isasymmetrically trapezoidal, and an upper surface of the lid is parallelto a plane of an upper edge of the rail and is located below bearings ofa rolling rail vehicle traveling on said rail.
 10. A casing according toclaim 8, wherein the casing base portion is formed from a region of atrough-shaped sleeper, the lid extends over the total width of thesleeper, as viewed in a longitudinal, direction of the rail, and the lidis fixed to the casing base portion.
 11. A casing according to claim 9,wherein the casing base portion is formed from a region of atrough-shaped sleeper, and the lid extends over a total width of thesleeper, as viewed in a longitudinal direction of the rail, and is fixedto the base portion.
 12. A casing according to claim 3, wherein theopening of the lid is configured to be covered with a closable cover.13. A casing according to claim 4, wherein the opening of the lid isconfigured to be covered with a closable cover.
 14. A casing accordingto claim 5, wherein the opening of the lid is configured to be coveredwith a closable cover.
 15. A casing according to claim 6, wherein theopening of the lid is configured to be covered with a closable cover.16. A casing according to claim 7, wherein the opening of the lid isconfigured to be covered with a closable cover.
 17. A casing accordingto claim 8, wherein the opening of the lid is configured to be coveredwith a closable cover.
 18. A casing according to claim 9, wherein theopening of the lid is configred to be covered with a closable cover. 19.A casing according to claim 10, wherein the opening of the lid isconfigured to be covered with a closable cover.
 20. A casing accordingto claim 11, wherein the opening of the lid is configured to be coveredwith a closable cover.